We measure the galaxy-galaxy lensing signal by stacking the tangential ellipticity
of source galaxies in projected radial bins
[1]}, [2]}, [3]}, [4]}, [5]}.
The non-zero tangential ellipticity, a.k.a the tangential shear (\(\gamma _{\rm t}\) )
is related to the excess surface density (ESD), \(\Delta \Sigma \) , by

(rp) = tcrit = (< rp) - (rp),

where \({\Sigma }(< r_{\rm p})\)  is the average surface mass density within
\(r_{\rm p}\) , \(\Sigma (r_{\rm p})\)  is the surface mass density at \(r_{\rm p}\) , and
\(\Sigma _{\rm crit}\)  is the geometrical factor defined as

crit = c24G DsDlDls(1+zl)2,

where \(c\)  is the speed of light, \(G\)  is the gravity constant, \(z_{\rm l}\)  is the redshift
of the lens, \(D_{\rm ls}\)  is the angular diameter distance between the lens and the source,
\(D_{\rm l}\)  and \(D_{\rm s}\)  are the angular diameter distances of the lens and the source,
respectively. In addition, we estimate the errors of the lensing signal by using 2,500 bootstrap samples.
